Answer:
42 = angle 4
Explanation:
angle 9 and angle 7 are vertical angles therefore they are both equal to each other and are 105 degrees.
angle 2 and angle 5 are vertical angles, so they are both 63 degrees.
angle 7 and the sum of angles 5 and 4 are alternate interior angles, so they are congruent, giving us the equation:
105 = angle 4 + 63
42 = angle 4